What was found
AIRCRAFT WAS GROUNDED. REJECTED TAKEOFF AT APPROXIMATELY 40 KNOTS, ENGINE NR 1 THRUST REVERSER LOCK ELECTRONIC CENTRALIZED AIRCRAFT MONITOR FAULT. ACCOMPLISHED TROUBLESHOOTING, PER TSM 78-31-00-810-863-A. NO FAULTS NOTED. PERFORMED A SATISFACTORY OPERATIONAL TEST OF THE THRUST REVERSER, PER AMM 78-31-00.